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authorUlrich Drepper <drepper@redhat.com>2001-07-16 06:29:42 +0000
committerUlrich Drepper <drepper@redhat.com>2001-07-16 06:29:42 +0000
commit3c204435e91ba20fbfef438e52fdc147e679ca58 (patch)
treef3cdbfd9405e6844b14d51b05974284ed902099d /sysdeps/s390/s390-64/bcopy.S
parenta6d214835f18ce3232d44ed6f0aba679d090693d (diff)
downloadglibc-3c204435e91ba20fbfef438e52fdc147e679ca58.tar.gz
Use mvcle for big blocks (> 64K) and a mvc loop for small blocks.
Diffstat (limited to 'sysdeps/s390/s390-64/bcopy.S')
-rw-r--r--sysdeps/s390/s390-64/bcopy.S18
1 files changed, 14 insertions, 4 deletions
diff --git a/sysdeps/s390/s390-64/bcopy.S b/sysdeps/s390/s390-64/bcopy.S
index bb3acdb708..ff7966723b 100644
--- a/sysdeps/s390/s390-64/bcopy.S
+++ b/sysdeps/s390/s390-64/bcopy.S
@@ -34,11 +34,13 @@ ENTRY(__bcopy)
jnl .L0
algr %r1,%r2
clgr %r1,%r3
- jh .L5
+ jh .L7
.L0: aghi %r4,-1 # length - 1
srlg %r1,%r4,8
- ltgr %r1,%r1
+ ltgr %r1,%r1 # < 256 bytes to move ?
jz .L2
+ cghi %r1,255 # > 1MB to move ?
+ jh .L5
.L1: mvc 0(256,%r3),0(%r2) # move in 256 byte chunks
la %r2,256(%r2)
la %r3,256(%r3)
@@ -47,8 +49,16 @@ ENTRY(__bcopy)
mvc 0(1,%r3),0(%r2) # instruction for execute
.L3: ex %r4,0(%r1) # execute mvc with length ((%r4)&255)+1
.L4: br %r14
-
-.L5: # destructive overlay, can not use mvcle
+ # data copies > 1MB are faster with mvcle.
+.L5: aghi %r4,1 # length + 1
+ lgr %r5,%r4 # source length
+ lgr %r4,%r2 # source address
+ lgr %r2,%r3 # set destination
+ lgr %r3,%r5 # destination length = source length
+.L6: mvcle %r2,%r4,0 # thats it, MVCLE is your friend
+ jo .L6
+ br %r14
+.L7: # destructive overlay, can not use mvcle
lgr %r1,%r2 # bcopy is called with source,dest
lgr %r2,%r3 # memmove with dest,source! Oh, well...
lgr %r3,%r1